Transfer of momentum .help needed ?

two particles of masses m1 & m2 are moving along a straight line with velocities u & v respectively. they collide to each other..if the collision between them is an elastic collision then show that momentum transfered from first particle to second particle is 2m1*m2(u - v)/m1 + m2....

2. Relevant equations

I am trying to use the condition of an elastic collision...their linear momentum & kinetic energy will be conserved..but the proof is not coming out....please help me with it.........

if the velocity of first particle after collision is u1 & the same of the 2nd particle is v1 then we know, u1 = (m1 - m2)*u/(m1 + m2) + 2m2*v/(m1 + m2)

v1 = 2m1*u/(m1 + m2) - (m1 - m2)*v/(m1 + m2)

3. The attempt at a solution1. The problem statement, all variables and given/known data